DWG to Blender, how can I import
Convert them in DXF

DWG is a cad standard format, but it's propetary so it's unlikely that you'll find a direct importer soon. I would save those file from the cad application in the DXF format and then import those.

Blender has a built in DXF importer that works quite well. You just have to enable it from the user preferences.